I begin most of my lectures by asking the audience to break up into pairs. Then I say this:

“Over the course of your life, you have excelled in part because of your impressive self-discipline. I want you to take all of the self-discipline you’ve been cultivating for the past couple of decades to do the following. For the next seven seconds, no matter what your partner says or does, I want you to show absolutely no emotional reaction. Go completely blank.”

I then ask the other person to simply look into his or her partner’s eyes and smile. I have done this experiment hundreds of times in corporate settings across the world, with everyone from nervous newbies to cantankerous lifers. The result is always the same. Virtually no one can refrain from returning their partner’s smile, and most break into laugher almost immediately.

Virtually no one can refrain from returning their partner’s smile, and most break into laughter almost immediately.

It doesn’t matter if I do this experiment during a week of massive layoffs or on a day when the stock market has plunged 600 points, I still see the same involuntary explosion of smiles. Even in parts of the world where smiling is less of a social norm, 80 to 85 percent of the participants cannot stop themselves from smiling.

If you think about this, it’s really pretty incredible. After all, if these people have the self-discipline and focus to work 10- to16-hour days, lead global teams and manage multimillion dollar projects, surely they can handle a task as simple as controlling their facial expression for a mere seven seconds, right? But the fact is, they can’t. Because something is going on in their brains that they aren’t even consciously aware of.

This mysterious force is the foundation of the ripple effect—the idea that your positive attitude and behavior quickly ripple out, increasing the happiness of everyone around you, changing the way your colleagues work and eventually shaping your entire organization.

Try this out for yourself: Spend a day smiling genuinely at every person you pass. Take note of their responses and watch the happiness factor spread throughout the room.